Fiber-blending apparatus



June 30, 1964 K. G. LYTToN ETAL R 25,609

FIBER-BLENDING APPARATUS 6 Sheets-Sheet 1 Original Filed April 13, 1953`lune 30, 1964 K, G, 'L YTTON ETAL Re. 25,609

FIBER-BLENDING APPARATUS 6 Sheets-Sheet 2 Original Filed April 13, 1953.QNGNE 7 [lll/lll Il] Ill/1l INVENTORS June 30, 1964 K, G, LYTTON ETALRe. 25,609

FIBER-BLENDING APPARATUS Original Filed April 13, 1953 6 Sheets-Sheet 4mi m Mm M m L/ Eff o Vy e W .m/fm, A www f m t S no. Jr n ek 6. www M/ um 7 7 Ke Phu M H|.||\ Lmfwjllw 1|) 8 Jnl H 8 w ,//6 W Il. 99 y l 6 4 8.afk 1| .Hf .6 4 a3 HHH n u ws P- 6 90% J6 |H ,IPG .n m om 0 O 0 aIT'ISQ/ MIJ 0 2 June 30, 1964 K G L YTTON ETAL Re. 25,609

FIBERfBLENDING APPARATUS 6 Sheets-Sheet 5 Original Filed April l5, 1953WMM, l(

June 30, 1964 K. G. LYTToN ETAL Re. 25,609

FIBER-BLENDING APPARATUS 6 Sheets-Sheet 6 Original Filed April 13, 1955m m T N um. m w o m a n @Bw A wmf nr, elm w unCc N NmN United StatesPatent O 25,609 FIBER-BLENDING APPARATUS Kenneth G. Lytton, Charles W.Barnes, and Cecil S. Wise, Gastonia, N.C., assignors to Fiber ControlsCorporation, Gastonia, N.C., a corporation of North Carolina OriginalNo. 3,071,202, dated Jan. 1, 1963, Ser. No. 348,406, Apr. 13, 1953.Application for reissue Nov. 26, 1963, Ser. No. 333,783

46 Claims. (Cl. 177-80) Matter enclosed in heavy brackets appears in theoriginal patent but forms no part of this reissue specification; matterprinted n italics indicates the additions made by reissue.

This invention relates to a system and apparatus for blending fibers,more especially textile fibers, by weight.

Modern fabrics frequently are made from yarn that is a blend ofdifferent types or grades of fibers, for example natural fibers, such aswool and cotton, and synthetic fibers, such as nylon, rayon, acetate,etc. Quite obviously, it is highly desirable to prepare a completelyhomogenized blend of the different bers making up any one particulartype of yarn in order to achieve complete uniformity of and avoidimperfections in fabric made therefrom. Such thorough blending is notalways achieved by known systems and apparatus, which blend fibers byweight, largely because the several different fibers going into thefinal blend are fed in haphazard batches into a continuously runningbeater type of mixer or blender.

Further, it obviously is highly desirable for a fiberblending system andapparatus to have a large capacity, i.e., the ability to blend a largequantity of fibers per unit of time. Fiber-blending apparatus andsystems presently in use do not have enough capacity.

Additionally, known apparatus for blending fibers by weight is notalways accurate and lacks the ability to maintain the desired blendproportions. Such shortcoming is due to imperfections in the weighingmechanism, which causes a considerable amount of hunting. The result is`a blend which varies from specifications.

Therefore, it is an object of this invention to provide an improvedfiber-blending system and apparatus that will feed different fibers intoa beater blender simultaneously and at uniform rates corresponding tothe predetermined proportions of the different fibers desired in thefinal blend, so that the blender or mixer serves to thoroughly mix andcompletely homogenize all of the fibers comprising each particular blendproduced by a run of the apparatus.

It is another object of this invention to provide a fiberblending systemand apparatus which fulfills the above object and also will feeddifferent fibers into a beater blender substantially continuously.

It is another object of this invention to provide an improvedfiber-blending apparatus which is accurate and will maintain the exactpredetermined desired proportions of the several different fibers makingup a selected blend.

It is a further object of this invention to provide an improvedfiber-blending apparatus which has a large capacity.

Other objects and advantages of the invention will be evident from thefollowing description and accompanying drawings in which:

FIGURE l is a plan view of a fiber-blending apparatus embodying thisinvention.

FIGURE 2 is an elevational view of the apparatus shown in FIGURE l, withthe chain drive cover plate removed to show details more clearly.

FIGURE 3 is an enlarged elevational view, partially in vertical section,of the apparatus shown in FIGURE 2.

FIGURE 4 is an enlarged fragmentary elevational `Reissued June 30, 1964View, with certain cover plates broken away and another removed, of aportion of one of the fiber-feeding machines illustrated in FIGURE 3.

FIGURE 5 is an enlarged fragmentary View taken substantially on line 5 5of FIGURE 2 and with cover plates being removed to show details.

FIGURE 6 is a view taken substantially on line 6-6 of FIGURE 5.

FIGURE 7 is a sectional view taken on line 7-7 of FIGURE 6.

FIGUR-E 8 is a sectional view taken on line 8-8 of FIGURE 7.

FIGURE 9 is an enlarged detailed fragmentary view taken on line 9 9 ofFIGURE 5.

FIGURE 10 is an enlarged detailed fragmentary view of the timing chainshown in FIGURE 2.

FIGURE 11 is a View corresponding to FIGURE 2 and illustrating amodified form of the invention.

FIGURE 12 is a wiring diagram of the electrical control system forapparatus embodying this invention.

FIGURE 13 is a wiring diagram of another type of electrical controlsystem for apparatus embodying this invention.

THE APPARATUS Referring now to the drawings, there is shown in FIGURES1, 2, and 3 a plurality of equally-spaced like fiber-feeding machinesF1, F2, and F3 arranged in a line and each driven by an electric motor(not shown). Although only three such machines F are shown in thedrawings, any number can be used, one for each different kind of fibergoing into the final blend. Such machines, commonly known as feeders,are Well-known in the art, so that no detailed description thereof isnecessary. It is sufficient to state that each machine F receives aseparate type or grade of fibers going into the blend and containsmechanism for elevating the fibers and discharging the same from adownwardly-facing elevated discharge opening in a discharge portion orspout 20 (FIGURE 5).

Running beneath the discharge spouts 20 of the machines F, for eventualreception and collection of fibers therefrom is a long endless beltconveyor 22 which feeds fibers deposited thereon into the inlet of aconventional continuous beater blender 24, that thoroughly mixes andblends the different fibers fed thereinto. As is also wellknown in theart, the beater blender 24 discharges the blended fibers into a tinter(not shown), from whence the blended fibers may be conveyed to a storagebin or a picker (not shown).

The belt of the collecting conveyor 22 is mounted on end rollers 26, 28having their shafts 30, 32 journalled in the upright side walls 34, 36of a trough-like housing 38. The conveyor belt is substantially as Wideas the housing 38 so that the walls 34, 36 prevent fibers from fallinglaterally off of the upper Hight of the belt. Desirably, similarlyjournalled intermediate rollers 40 support the upper and lower flightsof the conveyor belt between the end rollers 26, 28. The shaft 30 of theend roller 26 at the discharge end of the conveyor 22 projects throughthe side wall 34 and has a sprocket 42 mounted thereon (FIGURE 2). Adrive chain 44 engages the sprocket 42 and a sprocket 46 on the shaft ofan electric motor CM mounted on top of the housing 38 for driving theconveyor 22 in the direction indicated by the arrows. Disposed betweenthe side walls 34, 36, above the collecting conveyor 22 and directlybeneath the discharge spouts 20 of the feeding machines F, are aplurality of intermediate short equi-length endless belt conveyors DCI,DCZ, and DCS, one for each feeder F and each having end rollers 48, 50that are suitably journalled in the side walls 34, 36 of the housing 38.These intermediate or distributing conveyors are positioned to receivefibers from their corre- Ilength of each distributing conveyor.

sponding feeders and discharge such fibers onto the collecting conveyor22.

The rear roller shaft 52 of the distributing conveyor DC3 projectsthrough the side wall 34 of the housing 38 and has a sprocket 54 mountedthereon which is onehalf the diameter of the drive sprocket -42 of thecollecting conveyor 22. A chain 56 engages the sprocket 54 yand anothersprocket 58 of equal diameter mounted on the roller shaft 30 of thecollecting conveyor 22 to drive the distributing conveyor DC3 in thesame direction as and at a linear speed equal to one-half the speed ofthe collecting conveyor. Chains 60 also engage pairs of sprockets 62, ofthe same diameter as the sprocket 54,

4on the'rear roller shafts 52 of each pair of adjacent distributingconveyors DC to thereby drive all the distributing conveyors in the samedirection, i.e., the direction of .movement of the collecting conveyor22, and at the same speed, which speed is one-half the linear speed ofthe .lower conveyor.- Preferably, a removable cover plate 64 thedistance between the discharge ends of each pair of adjacentdistributing conveyors DC is equal to twice the Therefore, since thedistributing conveyors DC run at one-half the linear speed of the lowercollecting conveyor 22, a separate load or batch comprising apredetermined Weight of fibers deposited on each distributing conveyorfrom its corresponding machine F (as will be later described) will bedischarged therefrom at the rate which will distribute such loaduniformly over that section of the upper Hight of 'the collectingconveyor 22 extending between the discharge ends of each pair ofadjacent distributing conveylors.

Accordingly, if all such loads of different fibers are depositedsimultaneously on each distributing conveyor DC, the result will be asandwiching or stacking effect of the different bers on the collectingconveyor 22, wherein each separate load or batch thereon substantiallycoextensively overlies a batch of different bers previously depositedthereon by the adjacent distributing conveyor, as is best shown inFIGURE 3. Obviously these batches will then be so stacked at thedischarge end of the collecting conveyor 22 that all the different berswill be fed into the heater blender 24 simultaneously and `at a uniformrate corresponding to the predetermined proportions of the differentfibers desired in the final blend. Thus, the beaters of the blender 24repeatedly -cut through the stack to obtain a completely mixed uniformblend.

Variations in the above-described linear speed ratios of the collectingand distributing conveyors and in the spacing of the distributingconveyors are possible, but the distributing conveyors must be equallyspaced and the following relation must obtain:

wherein d equals the length of each of the batches deposited on thedistributing conveyors DC, v equals the linear speed of the distributingconveyors DC, D equals the distance along the collecting conveyorbetween the discharge ends of each pair of adjacent distributingconveyors, and V equals the linear speed of the collecting conveyor 22.

Further, it will be seen that, if the loads of bers are depositedsubstantially uniformly over substantially the entire length of theircorresponding distributing conveyors and the successive discharge ofloads of predetermined weight from the feeders is coordinated with thelinear speed of the distributing conveyors so that a succeeding load isdischarged from a feeder as the last of the preceding load is dischargedfrom the corresponding distributing conveyor, the sandwiched bers willbe fed into the blender in a substantially uninterrupted and continuousstream, as shown in FIGURE 3. Such a stream achieves more satisfactoryoperation of the beater blender 24. Apparatus for accomplishing theabove-described highly desirable mode of operation will now bedescribed.

Disposed beneath the discharge openings of the liberfeeding machinesF-are corresponding weighing mechanisms W1, W2, and W3 for directlyreceiving libers from the machines and discharging such libers inbatches of predetermined weight. All these weighing mechanisms W areidentical, so a description of one will suice for all. Each mechanism W(best shown in FIGURES 4 and 5) includes a weigh hopper or pan 66 thatis substantially rectangular in plan view and approximately coextensivein length, and preferably also in width, with its correspondingunderlying distributing conveyor DC. The pan 66 is suspended, bysuitable llexible straps 68 at each end thereof, from the parallel arms70 and 72 of a yoke-like scale beam 74 which straddles the dischargespout 20 or portion of the corresponding machine F. A cross member 76connects the two beam arms 70 and 72 behind the spout 20, and these beamarms are provided with projecting knife edge pivots 78 at the oppositeends of the cross member for pivotal support of the beam 74 within aring portion 80 of links 82. These links 82 depend from verticallyadjustable hooks 84 suspended on appropriate brackets 86 on thecorresponding fiber-feeding machine F. Extending rearwardly of the knifeedge pivots 78 is a counterbalance arm 88 having a large adjustablecounterweight 90 thereon and a threaded end on which is mounted a smallcounterweight 92 in the form of a nut for Vernier or fine balanceadjustment. For reasons later explained, the counterweights 90 and 92are adjusted to exactly balance the scale beam 74 when the weigh pan 66is empty.

Mounted for vertical slidable adjustment in a slideway 94 secured to theside of the fiber-feeding machine F directly above the ends of the beamarm 72 is an inverted U-shaped permanent magnet 96. The magnet 96 issupported by and straddles a horizontal bar 98 which projects outwardlyfrom a vertical slot in the front of the slideway 94 and has a verticalthreaded opening in its projecting end. A plate-like member 100 ismounted on top of the slideway 94, overhangs the projecting end of thebar 98, and has an aperture therein aligned with the opening in the bar.A headed screw 102 depends through the aperture in the plate 100 andinto threaded engagement with the opening in the bar 98, so thatadjustment of the screw serves to raise and lower the permanent magnet96. Preferably, a coil compression spring 104 (FIGURE 7) is interposedbetween the plate 100 and the bar l98 in surrounding relation with thescrew 102.

Secured to the top of an upstanding post 106 on the end of the beam arm72 is a metallic plate 108 in position to be attracted and held by thepermanent magnet 96. The plate 108 is of a size to abut against thelower edges of the slideway 94, so that in this latter position theforce of the magnetic attraction between the magnet and the plate can bevaried by vertical adjustment of the magnet by means of the screw 102.Thus, it will be seen that, when the counterweights 90 and 92 areadjusted to substantially exactly balance the scale beam 74 when thehopper 66 is empty and the magnet removed, the permanent magnet 96 maybe adjusted thereafter so that a predetermined weight of fibersdeposited in the hopper will cause the plate 108, together with thehopper, to drop away from the magnet.

An indicator arm 110 is pivotally mounted on the slideway 94 above thepermanent magnet 96 and has a camshaped end 112 resting against theupper surface of the latter, whereby the angular position of the armindicates the relative vertical position of the magnet. Preferably, ascale 114, which may have Weight indicia thereon, is secured to the sideof the feeder F and cooperates with a pointer 116 on the other end ofthe arm 110 to provide Y an indication of the weight of fibers necessaryto cause the weigh pan 66 to drop.

The bottom o-f the hopper 66 is closed by two dumping doors 118 whichare hinged to the opposite lower longitudinal edges of the hopper andnormally are barely maintained in closed position by adjustablecounterbalance weights 120, so that in the absence of doorclosingmechanism (later described) `a small weight of fibers in the hopperwould open the doors. Each door 118 is provided with end wings or flaps122 which overlie the corresponding ends of the hopper 66 when thedumping doors are closed. Mounted on both the wings 122 at one end ofthe hopper 66, as by appropriate bracket 124, are permanent bar magnets126, which are positioned in substantially parallel relation, but withtheir poles reversed, as shown best in FIGURE 5. Secured to the same endof the hopper 66, as by appropriate brackets 124, are permaend poles 128disposed to substantially contact the corresponding poles of the twopermanent magnets 126 when the dumping doors 118 are in closed position.Preferably, a cover plate 130 (FIGURES 2 and 3) is mounted on the hopperto enclose the mangets E and 126.

When current fiows through the electromagnet E in a direction so thatthe polarity of its two poles 128 is opposite from the polarity of theadjacent poles of the bar magnets 126, these latter permanent magnetswill be strongly attracted to the electromagnet E and, thus, hold thedumping doors 118 in closed position. When, however, current flowsthrough the electromagnet E in the opposite direction, its polarity willbe reversed and, thus, strongly repel the permanent magnets 126 so thatthe dumping doors 118 will be flung Wide open. When the doors 118 havebeen so opened and the fibers in the hopper 66 accordingly dischargedonto the distributing conveyor DC, the door counterbalance weights 120swing the doors back toward closed position, and, if the polarity of theelectromagnet E is again reversed, the dumping doors will swing rapidlyback to closed position and be strongly maintained in this position bythe attraction of the electromagnet.

A bar 132 extends laterally from the side of the discharge spout of thefeeder F, beneath and adjacent the forward end of the beam arm 72.Threaded upwardly through this bar 132 and having a lock nut 134 thereonis a stop screw 136 (FIGURES 4 and 9) having its upper end disposed aslight distance beneath the beam arm 72. By means of this construction,when a weight of fibers sufficient to pull the plate 108 away from themagnet 96 has been discharged from the feeder F into the hopper 66, thehopper and its supporting scale beam 74 drop only a slight distancebefore being stopped by engagement of the beam arm 72 with the top ofthe stop screw 136. Hence, the plate 108 is not removed from theattractive field of the magnet 96. Also threadedly engaged with thelateral bar 132, outwardly of the stop screw 136, is a verticallyadjustable screw 138, having a lock nut 140 thereon, for cooperationwith a wire actuating arm 142 of a weigh switch WS, preferably amicro-switch, having a set of normally-closed contacts. The switch WS isclosed when the scale beam 74 is held in its up position by thepermanent magnet 96 and is open when the scale beam drops. Preferably,cover plates 144 (FIGURES 1, 2, 3, and 4) are mounted on the spout 20 toenclose the scale beam 74, the magnet 96 and its slideway 94, and thelateral bar 132.

Referring to FIGURE l of the drawings, it will be seen that a thirdsprocket 146, of the same diameter as the sprockets 54 and 62, ismounted on the roller shaft 52 of the distributing conveyor DC3. Engagedwith the sprocket 146 and running over a sprocket 148 journalled on abracket 150 adjustably mounted on the side of the housing 38 is a timingchain 152, which is exactly half the length of the endless belts of thedistributing conveyors DC. A timing or dump switch DS having a set ofnormally-open contacts and a set of normally-closed contacts is securedto lthe side of the housing 38 and is provided with a pivoted actuatingarm 154 positioned to be engaged by a single lug 156 on the chain, asbest shown in FIGURE 10. By reason of this construction, it will be seenthat the switch DS will be actuated twice during each complete cycle ofthe distributing conveyors DC, i.e., actuated each time the distributingconveyors travel a distance equal to their length. The reason for thisconstruction will be described more in detail hereinafter.

THE ELECTRIC CONTROLS A description of the operation of theafore-described fiber-blending apparatus may best be understoodby-reference to FIGURE l2 of the drawings. The electric motor CM whichdrives both the collecting and distributing conveyors 22 and DCpreferably is of three-phase type and provided with power from threeconductors 158 that are connected to any suitable source of power, eg.,550 v. 3-phase. The motor CM is controlled by a relay CR having threesets of normally-open contacts connected in series with the conductors158. Preferably, the conveyor motor CM is provided with a conventionalelectromagnetic brake (not shown) that is automatically released whenthe motor is energized and automatically set when the motor isdeenergized. The electric motors FMI, PM2, and FMS which drive thefeeders F are likewise of three-phase type and provided with automaticbrakes (not shown) like the auotomatic brake of the conveyor motor CM.The feeder motors FM are connected to the same three-phase power sourceas the conveyor motor CM, by conductors 160, and are controlledindividually by feeder motor relays FRI, FR2, and FR3, each having threesets of normally-open contacts connected in series with the conductors160 and one set of normally-closed contacts. These sets ofnormally-closed contacts are all connected in series in a circuit forreasons later explained.

The dumping-door-controlling electromagnets E of each feeder F areconnected in parallel with conductors 162 (by suitable flexibleconductors) for simultaneous operation and are supplied with directcurrent from a rectier R. The rectifier is supplied with power, viaconductors 164, from two conductors 166 that are connected to anappropriate source of power, e.g., v. single-phase A.C. The conductors166 also supply power to the energizing coils of all the various relaysof the electrical control system.

In order to control the direction of current flow through theelectromagnets E, there is provided a current-reversing or dumping relayDR, having two sets of normallyopen and two sets of normally-closedcontacts appropriately connected between the rectifier R and theconductors 162. Preferably, a variable resistance V is connected inseries between the rectifier R and one of the sets of contacts of therelay DR in order to provide a differential between the door-opening anddoor-closing forces exerted by the electromagnets E. The control systemalso includes a safety relay SR having two sets of normally-opencontacts, and a time-delay relay TR having a set of normally-closedcontacts. The time-delay relay TR is of the delayed-closing type and isadjusted to obtain about three to five seconds delay in the closing ofits contacts after de-energization of its energizing coil. As describedabove, the control system also includes the timing or dump switch DSthat is operated by the lug 156 on the timing chain 152 and has a set ofnormally-open contacts and a set of normally-closed contacts. Also aspreviously described, weigh switches WSI, WS2, and W83 are associatedwith the Weighing mechanisms W and each has one set of normally-closedcontacts that are opened by descent of the corresponding Weigh pan 66upon its receipt of a predetermined weight of fibers.

The feeders are each separately controlled by manually-operablesingle-pole double-throw switches FSl, F52, and FSS, each having threepositions: manual, off, and automatic. Further, the control system mayinclude a picker demand limit switch PS having a set of normallyclosedcontacts. This switch PS may be associated with a supply bin or hopper(not shown) for a picker, and is adapted to be opened when such bin isfull, so that the entire apparatus will be shut down and no fibers willbe supplied to the picker supply bin. When, however, the supply bin isnot full, the picker demand limit switch PS is closed and the apparatuswill run and supply fibers to the picker. The switch PS can also beassociated with a conduit for pneumatically conveying fibers to a pickerand achieve the same result, the switch being adapted to be open whenair is carrying fibers through the conduit and to be closed when no airis iiowing through the conduit. The controls also include a single-polesingle-throw manually-operable conveyor switch CS connected in serieswith the picker demand limit switch PS for manually stopping theoperation of the conveyor motor CM.

OPERATION Assuming that all three of the feeders F are shut off and thatthe picker is calling for fibers so that the picker demand limit switchPS is closed, the first step is to close the conveyor switch CS whichcloses a conveyor-motoractuating circuit, via conductor 168, switch PS,conductor 170, switch CS, conductors 172, 174, and 176, thenormally-closed contacts of the dump switch DS, conductor 178, the coilof the relay CR, and the conductor 180. This circuit, when closed,energizes the conveyor relay CR and thereby closes its contacts t0 startthe motor CM to drive the conveyors. It also will be noted that lclosingthe conveyor switch CS also closes a safety-relayenergizing circuit viaconductor 168, switch PS, conductor 170, switch CS, conductors 172 and182, coil of relay SR, conductor 184, normally-closed contacts of relayFR3, conductor 186, normally-closed contacts of relay FR2, conductor188, normally-closed contacts of relay FRl, and conductor 190. When thiscircuit is so closed, the relay SR is energized and both sets of itscontacts closed to also close an alternating conveyor-motor-actuatingcircuit via conductor 168, switch PS, conductor 170, switch CS,conductors 172 and 192, a set of the normallyopen contacts of relay SR,conductors 194 and 178, coil of relay CR, and conductor 180.

The control switch FSI for feeder F1 is then moved to automatic positionA to thereby close an actuating circuit for feeder motor FM1, viaconductor 196, the

normally-closed contacts' of the time-delay relay TR,

conductors 198 and 200, coil of relay FRI, conductor A202, weight switchWSI, conductor 204, switch FSI, conductors 206, 208, 174, and 172,switch CS, conductor '170, switch PS, and conductor 168. When thiscircuit is closed, the feeder motor relay FRI is energized to close itsthree sets of normally-open contacts and thereby start the motor FM1 forthe fiber-feeding machine F1. It will be noted that, when any of therelays FR are energized, its set of normally-closed contacts is open tothereby interrupt the aforedescribed safety-relay-energizing circuit andthus also interrupt the alternative conveyor-motoractuating circuit. Thefeeder F1 then delivers fibers to its weight pan 66, and, when apredetermined weight of fibers has been received therein, the weight pandrops, thus opening the contacts of the weight switch WSI to open theaforedescribed feeder-motor-actuating circuit and de-energze the relayFRI to stop the motor F M1 and the feeding of further fibers into theweight pan. Since all of the relays FR are then de-energized, thesafetyrelay-energizing circuit is again closed, so that the alternativeconveyor-actuating circuit is also closed.

When the lug 156 on the timing chain 152 actuates the dump switch DS, adump-relay energizing circuit is closed, via conductors 180 and 210, aset of contacts of the safety relay SR, conductors 212 and 214, coil ofrelay DR, conductor 216, the normally-open but now closed contacts ofswitch DS, conductors 174 and 172, switch CS, conductor 170, switch PS,and conductor 168. Thus, the dump relay DR is energized and reverses thedirection of current flowing through the electromagnet E1 (and also theelectromagnets E2 and E3) and dumps the fibers contained in the weighpan of feeder FI onto the distributing conveyor DCI, from whence thefibers are discharged onto the collecting conveyor 22. Thereupon, theweight pan 66 rises and is held in its uppermost position by theattraction of the plate 108 by the permanent magnet 96. At the sametime, the rising of the weight pan closes weight switch WSI to againclose the feeder-motor-actuating circuit which starts operation of themotor FM1 to discharge fibers into the weigh pan and at the same timeinterrupts the safety-relay-energizing circuit.

It will be noted that, when the dump switch DS is actuated by the lug156, the conveyor-motor-actuating circuit is interrupted, but, if thesafety-relay energizing circuit is closed, the alternativeconveyor-motor actuating circuit is also closed so that all theconveyors continue to run. In the event, however, that the weigh pan 66has not received its predetermined weight of fibers when the lug on thetiming chain actuates the dump switch DS, the relay FRI is stillenergized and holds open its normally-closed set of contacts.Accordingly, the safety-relay-energizing circuit is open, and, thus thealternative conveyor-motor-actuating circuit is open, as well as thedump-relay energizing circuit. Hence, the conveyors stop and the weighpan 66 will not be dumped until the latter receives its predeterminedweight of fibers and drops to open the contacts of the weigh switch WSto thereby interrupt the feeder-motor-actuating circuit and close thesafety-relay-energizing circuit.

After the feeder F1 has been started in accordance with the foregoingdescription and has dumped a load of fibers on the distributing conveyorDCI, the machine F2 is started by moving the switch FS2 to automaticposition A, to thus complete an actuating circuit for the feeder motorFM2, which energizes relay FRZ via conductor 196, contacts of relay TR,conductors 198 and 218, coil of relay FR2, conductor 220, weigh switchWS2, conductor 222, feeder switch PS2, conductors 224, 208, 174, and172, switch CS, conductor 170, switch PS and conductor 168. Hence, themotor PM2 starts and the feeder F2 discharges fibers into its weigh pan66. In the event that the weigh pan of either or both feeders F1 and F2does not fill up with its predetermined weight of fibers prior to thetime that the timing lug 156 again actuates the dump switch DS, thenormally-closed contacts of either or both of feeder motor relays FRIand FR2 will be open to thus interrupt the safety-relay-energizingcircuit, so that the conveyors will be brought to a halt, as abovedescribed. Again, when the weigh pans of both feeders F1 and F2 havereceived their predetermined weights of fibers and have dropped tothereby open the switches WSI and WS2, the relays FRI and FRZ will bede-energized to stop the further feeding of bers from the feeders, and,when the last feeder to discharge its quota stops, the safety relay SRwill be energized to thereby simultaneously discharge fibers from theweigh pans of both feeders F1 and F2 onto their correspondingdistributing conveyors DCI and DC2, at the same time or rather shortlythereafter, as later described, the conveyor-motor-actuating circuit isclosed to start the operation of all of the conveyors.

The remaining fiber-feeding machine F3 is started in the same mannerafter the fiber-feeding machine F2 has dumped its initial load of fiberson the distributing conveyor DC2, so that by the successive starting ofall of the fiber-feeding machines F1, F2, and F3 the initiallydischarged loads of fibers of all the feeders arrive at the dischargeend of the collecting conveyor 22 in the desired stacked or sandwichedarrangement shown in FIG- URE 3. Thereafter the feeders will continue torecycle, so that the different fibers will be fed into the beaterblender in a sandwiched continuous stream. At the end of a run, thefeeders are stopped in the same sequence by moving their respectiveswitches FS to off position O, so that no batches are fed separatelyinto the beater blender 24 Without being stacked or sandwiched withcorresponding batches from all the other feeders.

It will be seen that the energizing coil of the timedelay relay TR isconnected in parallel with the energizing coil of the dump relay DR byconductors 214 and 226, `so that whenever the later relay is energized,the relay TR is also energized. Thus, after the weigh pans of theseveral feeders F have discharged their. batches or loads of fibers onthe distributing conveyors DC and rise to close the weigh switches WS,the feeder-motoractuating circuits will not be closed until a fewseconds after the de-energization of the dump relay DR and thetime-delay relay TR. Accordingly, because of this delay in thereenergization of the feeder motor relays FR, there is suicient time forthe dumping doors to close and be held shut and for all the weigh pansto rise and to be securely held in their up position by their respectivepermanent magnets 96 before the feeder motors FM start. There is thusavoided any possibility of false starts of the motors FM by prematureclosing of the weigh switches WS before their corresponding weigh pansare firmly held in their up position by the permanent magnets before allthe dumping doors are closed. Hence, hunting of the weighing mechanismsW cannot occur.

After all of the feeders F have been started as outlined above, thesandwiched batches of fibers will be fed in a continuous anduninterrupted stream into the beater blender at a rate which is limitedonly by the fparticular feeder F which requires the longest interval oftime to fill and dump its weigh pan. Hence, for maximum capacity thelinear speed of the conveyors 22 and D.C. should be regulated so thatthe distributing conveyors will travel a distance only slightly lessthan onehalf of their cycle during the aforedescribed limiting timeinterval. The reason for this slight discrepancy in distance travelledis to avoid any pausing of the conveyors; as outlined above, during eachcycle of operation of the feeders F and to keep the conveyors runningcontinuously for smoother operation of the apparatus.

In the event that it is desired to test the weighing mechanisms of themachines individually without operation of the conveyors, the conveyorswitch CS is opened and the control switch FS of the feeder which isdesired to be tested, for example, feeder F1, is moved to its manualposition M, while the switches of the other feeders are moved to offposition O. In this position of the switch FS1, an alternativefeeder-motor-actuating circuit will be closed, via conductor 228, switchFSl, conductor 204, weigh `switch WSI, conductor 202, co-il of relayFR1, conductors 200 and 198, controls of time-delay relay TR, and theconductor 196, to thus energize the feeder motor relay FR1 and start thefeeder motor FM1. Thereupon, the machine F1 will run and discharge apredetermined and adjustable quantity of fibers into its correspondingweigh pan, and, upon opening of the weigh switch WS1 upon descent of thepan, the feeder F1 will stop. The fibers will not be dumped, however,unless the lconveyor switch CS is closed to cause the dump switch DS tobe actuated by the timing lug 156 to close the energizing circuit forthe dump control relay DR. This manual position M of the feeder switchesFS of the machines F is obviously used only for the purposekof enablingvarious` quantities of fibers to be discharged into the weigh pans priorto a run in order to accurately adjust the permanent magnets for apredetermined weight setting.

MODIFICATION OF THE APPARATUS Referring now to FIGURE 11 of thedrawings, there is shown therein apparatus which serves to feeddifferent iibers into a beater blender 24 simultaneously and at uniformrates corresponding to the predetermined proportions of the differentfibers desired in the final blend, but which does not feed such fibersin a continuous and uninterrupted stream. In this embodiment, there areprovided a plurality of equally spaced liber-feeding machines, four suchmachines, F1, F2, F3, and F4, being shown in the drawings, eachidentical with and having exactly the same type of weighing mechanism Was has been heretofore described. There are no intermediate ordistributing conveyors, but instead of feeders F dump their equi-lengthbatches simultaneously and in spaced relation directly onto a collectingconveyor 230 disposed in a housing 231, similar to the housing 38previously described. This iconveyor 230 is driven, as in the previouslydescribed embodiment, by an electric motor CM having a chain 232 engagedwith a sprocket 234 on the motor shaft and with a sprocket 236 on theshaft 238 of the roller at the discharge end of the collecting conveyor.As before, the fiber-feeding machines F are equally spaced along theconveyor 230 and controlled by a system of electrical controls identicalto those shown in FIG- URE 12.

A sprocket 240 of a diameter equal to one-half that of the frontconveyor roller 242 is mounted on the front roller shaft of the conveyor230 and has a timing chain 244 engaged therewith, which runs overanother sprocket 246 journalled on a bracket adjustably mounted on theside wall of the housing 231. A dump switch DS for the electricalcontrols, and which is identical in construction with the dump switchDS, is secured to the side of the housing 231 and has its actuating armpositioned to be engaged by a single lug 248 on the chain 244. The chain244 is of a length equal to one-half the distance between correspondingends of adjacent spaced batches of fibers deposited on the collectingconveyor 230; i.e., the chain length is equal to one-half a distanceequal to the length of a batch plus the distance between adjacentbatches. Because of the relative diameters of the sprocket 240 and theroller 242, it will be seen that the chain runs at a speed equal toone-half of the linear speed of the collecting conveyor.

Hence, since the batches of fibers are dumped simultaneously on theconveyor, the lat-ter travels a distance equal to the distance betweencorresponding ends of spaced adjacent batches before a succeeding batchis dumped, so that each batch of fibers deposited on the collectingconveyor substantially coextensively overlies the ybatch previouslydeposited thereon by the adjacent fiber-feeding machine. It will againbe seen that the relation of obtains, wherein d equal the length of thetiming chain (or the distance between equally-spaced switch-trippinglugs thereon), v equals the linear speed of the timing chain instead ofthe linear speed of distributing conveyors, D equals the distancebetween corresponding ends of spaced batches deposited on the collectingconveyor, and V equals the linear speed of the collecting conveyor.

In this embodiment, it will be seen that the batches are stacked on thecollecting conveyor 230 and fed in separate groups into the beaterblender, which again makes for a thoroughly mixed and homogenized iinalblend.

By a very siinple change in the length of the timing chain 244 (or bymounting more than one switch-tripping lug 248 thereon) and by properlyspacing the feeders F, the apparatus shown in FIGURE 11 can be adaptedto feed fibers in a substantially continuous and uninterrupted stream.Thus, it will be seen that if the feeders F are spaced apart a distanceso that the spacing between their respective weigh pans is substantiallyequal to multiples of the lengths of the dumped batches or loads offibers, and the dump switch DS is periodically actuated after thecollecting conveyor 230 has moved a distance equal to the length of abatch of fibers deposited thereon, the result will be the feeding of asubstantially continuous and uninterrupted stream of bers into thebeater blender 24. Thus, for'example, if the feeders F shown in FIGURE11 are spaced so that the distance between their weigh pans issubstantially equal to the length of a load of fibers deposited on theconveyor 230, two equally-spaced lugs 248 may be mounted on the chain244 (or a single lug 248 may be used with a chain which is one-half ofthe length of chain 244), so that after the conveyor 230 has travelled adistance equal to the length of a. batch of fibers thereon, the dumpswitch DS' will again be actuated. Hence the ends of the fiber loadsdumped from any one feeder F will be substantially contiguous. In thismodification, after the feeder F1 has been started the feeder F2 is notstarted until the feeder F1 has dumped two loads on the collectingconveyor 230, and the feeder F3 is not started until after the feeder F2has dumped two loads on the collecting conveyor 230, etc.

The result of this construction is to fill up the blank spaces betweenthe loads shown in FIGURE l1, so that there is a constant anduninterrupted stream of sandwiched fibers being fed into the beaterblender 24.

MODIFICATION OF THE ELECTRICAL CONTROLS Referring now to FIGURE 13 ofthe drawings, there is shown a wiring diagram which can be used tooperate 4any of the aforedescribed apparatus embodiments and pans, stop,and dump independently of each other. When the last of the feeders toreceive its quota has stopped and dumped its load or batch of fibersindependently of the other feeders, the feeders remain stopped while theconveyors start. After the conveyors have run a predetermined distance,corresponding to the distance necessary to achieve the aforedescribedstacking or sandwiching of the batches from the several feeders on thecollecting conveyor, the conveyors again pause while the feeders againrun, stop, and dump their batches of fibers independently.

The electrical apparatus for achieving this system of operation againincludes three conductors 250 for providing three-phase power to theconveyor motor CM, which is controlled by a conveyor motor relay CR. Thefeeders F1, F2, and F3 are operated by corresponding feeders motor FMI,PM2, and FM3, that are controlled by corresponding feeder motor relaysFRI, FR2, and FR3, each having four sets of normally-open contacts. Thefeeder motors FM are supplied with power by three conductors 252 thatare connected to the conductors 250 in advance of the contacts of therelay CR. Again, all of the motors CM and FM preferably are providedwith `conventional electromagnetic brakes, the same as described withreference to FIGURE l2. The dumpingdoofr-controlling electromagnets E1,E2, and E3 of the feeders F are supplied with direct current from arectifier R, which, in turn is supplied with power, via conductors 254,from two conductors 256 that are connected to an appropriate source ofpower; c g., 110 v. single-phase .A.C. These two conductors 256 alsosupply power to the energizing coils of all of the various controlrelays.

The direction of current ow through each electromagnet E is controlledindependently of the others, however, vby separate dumping relays DR1,DR2, and DR3, one for each feeder F, and each having three sets ofnormallyclosed and two sets of normally-open contacts. The two sets ofnormally-open contacts and two of the three sets of normally-closedcontacts of the relays DR are appropriately connected between therectifier R and the corresponding electromagnets E by the conductors 258for reversing current flow through the electromagnets by operation ofthe relays. Again, a variable resistance V is connected in series withone of the conductors 258, so that a differential may be achieved, ifdesired, between the holding and repelling forces of the electromagnetswith respect to the dumping doors of the weigh pans 66.

The control system for 'the feeders F also includes the weigh switchesWS1, W82, and W83, one for each feeder, and each having two sets ofnormally-closed contacts; i.e., closed when the corresponding weigh panis in its elevated or raised position. The feeders also havecorresponding energizing relays ER1, ER2, and ERS, each having two -setsof normally-open and one set of normally-closed contacts, and thecorresponding manuallyoperable, single-pole, double-throw switches FS1,FS2, and FSS, each having three positions-automatic A, off O, and manualM. The control system also includes two time-delay relays TR1 and TR2,relay TR1 having a set of normally-open contacts, and relay TR2 having aset of normally-closed contacts. The relay TR1 delays in both openingand closing its contacts, while the relay TR2 delays only in opening itscontacts. A safety relay SR having a set of normally-closed and two setsof normallyopen contacts is also provided. Further, the control systemincludes a timing or conveyor stop switch SS having a set ofnormally-closed contacts and provided with an actuating element that isadapted to be engaged by the lug 156 on the timing chain 152 for openingthe switch.

The system may also include a picker demand limit switch PS, which has aset of normally-closed contacts and performs the same functions andoperates in the same manner as the picker demand limit switch describedabove with reference to FIGURE 12. Again, connected in series with thepicker demand limit switch PS is a manually-operable conveyor switch CS.In addition to the foregoing controls, the system may include amanually-operable dump switch DS of the push button type having a set ofnormally-closed contacts. The functions of this switch will be describedmore in detail hereinafter.

OPERATION WITH MODIFIED ELECTRICAL CONTROLS Assuming that all three ofthe feeders F are shut off, i.e., the switches FS are all in off Oposition, and that the picker is calling for fibers so that the pickerdemand limit switch PS is closed, the first step is to move the switchFSI for the feeder F1 to automatic A position and to close the conveyorswitch CS. This latter switch closes a safety-relay-energizing circuit,via conductor 260, coil of relay SR, conductors 262 and 264, switch CS,conductor 266, switch PS, conductor 268, a set of now closed butnormally-open contacts of relay ER1, conductor 270, a set ofnormally-open but now closed contacts of relay [cuit] circuit, viaconductor 280, a set of normally-open but now closed contacts of relayERS, conductor 274, conductor 276, the set of normally-closed contactsof relay SR, conductor 278, and conductor 280. It will be noted thatthis circuit is self-interrupting because of the inclusion of the set ofnormally-closed contacts of the relay SR. A

lsafety-relay-holding circuit is provided, however, to maintain therelay SR energized, such circuit including conductor 260, coil of relaySR, conductors 262 and 282, a set of normally-open contacts of relay SR(adjusted to close before the set of normally-closed contacts open),conductor 2184, stop switch SS, and conductor 286.

When the relay SR is thus energized and held in by its holding circuit,another set of its normally-open contacts is closed to thereby close aconveyor-motor-actuating circuit, via conductor280, a set ofnormally-open but now 294, the parallel-connected coils of relays TR1and TR2, conductor 296, and conductor 298. Energization of the relay SRalso interrupts the energizing circuit of all the dump relays DR. Sincethe circuits for the several feeders include several sets ofparallel-connected sections, one set for each feeder, a description ofthe circuits for one feeder, for example, F1, will suilce for all. Inthis manner the energizing circuit for the dump relay DRI includesconductors 280 and 278, the normally-closed contacts of relay SR,conductor 276, the dump switch DS, conductors 300 and 302, coil of relayDR1, conductor 304, a set of normally-closed contacts of the weighswitch WSI, conductor 306, and conductor 308. Upon de-energization ofthe relay DRI, the dumping doors of the feeder F I are open.

It will be noted that, prior to closing the conveyor switch CS, theenergizing circuit of the tirne-delay relay TR1 is closed, so that therelay TR1 is energized and its contacts are closed. The contacts ofrelay TR1 are included in a holding circuitfor the energizing relay ERI,which circuit includes conductors 31.0 and 312, the contacts of relayTR1, conductors 314 and 316, a set of normally-open contacts of therelay ERI, conductors 318 and 320, coil of the relay ERI, conducto-r322, and conductor 324. Since the contacts of relay TRI delay inopening, however, there is a delay in the interruption of the holdingcircuit for the relay ERIafter the conveyor switch CS is closed, andbefore this interruption the energizing circuit for the dump relay DRIis opened, to thus close its three sets of normally-closed contacts. Oneset of these contacts is included in an energizing circuit for theenergizing relay ERI, which circuit includes conductors 324 and 322,coil of relay ERI, conductors 320 and 318, a set of normally-closedcontacts of dump relay DRI, and conductor 326. Accordingly, theenergizing circuit for the energizing relay ERI is closed when theenergizing circuit for the relay DRI is interrupted to thus maintain therelay ERI energized.

As long as the relay ERI is energized, it will be noted that theenergizing circuit for the feeder motor relay FRI is open, such circuitincluding conductors 328 and 330, coil of relay FRI, conductors 332,334, and 336, the set of normally-closed but now open contacts of relayERI, conductors 338 and 340, the contacts of time-delay relay TR2,conductor 312, and conductor 310. Therefore, the feeder motor relay FRIcannot be energized to start the feeder motor FMI until the relay ERIhas been deenergized.

The above conditions will prevail; i.e., the conveyors will run, dumpingdoors of the weigh pans of the several machines will be open, and thefeeder F1 will not run until the holding circuit for the safety relay SRis interrupted by actuation of the stop switch SS by the lug 156 on thetiming chain.

Substantially simultaneously with the interruption of the holdingcircuit for the relay SR, the energizing circuits for the time-delayrelays TRI and TR2 for the dump relay DR1 are closed by thede-energization of the relay SR. Energization of the relay DR1interrupts the energizing circuit for the relay ERI and, since thecontacts of the time-delay relay TRI also delay in closing, the holdingcircuit for the relay ERI is not closed prior to its energizing circuitbeing opened. Hence, the relay ERI is de-energized and closes theenergizing circuit for the feeder motor relay FRI, as well as openingthe energizing circuit for relay SR, so that the conveyor stops. Sincethe delayed-opening contacts of the relay TR2 are included in theenergizing circuit for the feeder motor relay FRI, this circuit will beclosed only long enough for energization of the relay FRI. Energizationof this relay FRI, however, closes a holding circuit therefor Whichincludes conductors 328 and 330, coil of relay FRI, conductors 332 and334, a set of the normally-open but now closed contacts of the relayFRI, conductor 342,

switch FSI when in automatic position, conductor 344, a set ofnormally-closed contacts of switch WSI, and conductors 346, 306, and30S. Hence, the feeder F1 runs and delivers fibers to its weigh panwhile the conveyors pause. l

When the feeder FI has delivered its predetermined weight of fibers intoits weigh pan, the latter drops and thereby opens both sets of contactsof its weigh switch WSI to thereby interrupt both the holding circuitfor the feeder motor relay FRI and the energizing circuit for the dumprelay DRI. Accordingly, the feeder motor relay FRI is cle-energized tothereby stop the operation of the feeder motor FMI, to cease furtherdelivery of the fibers into the weigh pan. \\At the same time, thede-energization of the dump relay DRI reverses the direction of circuitflow through the electromagnet EI and thereby dumps the bers from theweigh pan onto the distributing conveyor DCI. At the same time, thede-energization of the relay DRI closes the energizing circuit for therelay ERI, and the energization of relay ERI closes the energizingcircuit for the relay SR. Energization of this latter relay closes theconveyor-motor-actuating circuit and the conveyors start to run.

After the initial load from feeder FI has thus been dumped and theconveyors start to run, the feeder control switch FS2 is moved toautomatic position A, so that when the lug 156 on the timing chain againinterrupts the holding circuit for the relay SR, the holding circuitsfor both feeder motor relays FRI and FR2 will be closed to therebypermit both feeders FI and F2 to operate and complete their filling,dumping, and stopping cycles. Likewise, after feeders FI and F2 havebeen started, as heretofore described, feeder F3 is started in the samemanner by moving its control switch FS3 to automatic position A.Thereupon, the conveyors will run a predetermined distance and stop;each feeder will independently complete its filling, dumping, andstopping cycle; and upon the stopping of the last feeder to dump, theconveyors will again be driven because of the closing of thesafety-relay-energzing circuit.

At the end of a run the several feeders are stopped in the same sequencefor the same reason described above with reference to the electriccontrols shown in FIG- URE 12.

It will be seen that the feeders F will recycle automatically only whentheir control switches FS are in automatic position A to thereby enablethe several holding circuits for the feeder motor relays FR to becompleted. In the event that it is desired to Weigh test any one of thefeeders while the entire apparatus is shut down, the control switch FSof the desired feeder F, for example, FI, is moved to manual position M,thereby completing an alternative feeder motor relay energizing circuit,which circuit includes conductors 328 and 330, coil of relay FRI,conductors .332 and 334, switch FSI when in M position, conductor 344, aset of normallyclosed contacts of weight switch WSI, and conductors 346,306, and 308. Of course, energization of the feeder motor relay FRIstarts feeder motor FMI, and the feeder F1 will fill its Weigh pan,drop, and dump. The feeder FI will thus continue to recycle, withoutoperation of the conveyors, as long as the switch FSI is in M position.

In the event it is desired to dump the weigh pan of any of the feedersbeing so tested before sufficient fibers have been received in the panto cause it to drop and open the corresponding weigh switch WS, the dumpswitch DS is opened, thereby interrupting the dump relay energizingcircuits.

It will thus be seen that the objects of this invention have been fullyand effectively accomplished. The different fibers going into the finalblend are fed simultaneously and at uniform rates into the beaterblender. Hence, the nal blend is a completely homogenized mixture of theseveral different fibers. The apparatus also operates at relatively highspeed, in that about 330 loads or batches per hour can be dischargedfrom each feeder. Such large capacity is due largely to the uniqueweighing apparatus, which, though quite sensitive to the small weightsinvolved (a range of about 4 to 20 ounces), operates smoothly andrapidly without any hunting whatever. Moreover, the weighing apparatusis extremely accurate since the scale beam does not move until, anddrops abruptly only when, the predetermined weight of fibers is receivedin the corresponding weigh pan and the automatic brakes on the feedermotors provide a sharp delivery cut-off. Additionally, since thevertical distance travelled by the weigh pan is quite small, upon thedumping of a load the weigh pan can be rapidly repositioned for thereception of another batch of fibers therein. In this connection it willbe noted that, since the magnetic plate 108 is never cornpletelyWithdrawn from the field of magnetic attraction of the permanent magnet96, the permanent magnet quickly draws the weigh pan back intofiber-receiving position upon the dumping of a load. Further, it will benoted that, because the dumping doors of the weigh pan are forcefullyflung open by reversal of the current through the electromagnet, thefibers are dumped more rapidly than would be possible by the mereunlatching of a dumping door for gravity opening thereof by a weight offibers in the Weigh pan. Additionally, the door opening and closingmechanism functions extremely smoothly and without undue jarring.

It will be realized that the specific embodiments shown and described toillustrate the principles of this invention are subject to modificationwithout departing from such principles. Therefore, this inventionincludes all modifications encompassed within the spirit and scope ofthe following claims.

We claim:

l. Material-blending apparatus comprising: movable collecting conveyormeans; automatic and continuallyoperating means for depositing inrepetitive cycles a plurality of separate loads of different materials,each of a predetermined weight, on separate equilength sections of saidconveyor means; and means correlating the operation of said depositingmeans with the operation of said conveyor means to cause each said loadto be deposited in substantially coextensive overlying relation with aload previously deposited on a section of said conveyor means by anadjacent depositing means, said correlating means including an electriccircuit and means affecting the energization of said circuit each timesaid conveyor means moves the same predetermined distance.

2. The structure defined in claim l in which the conveyor means operatescontinuously, the depositing means effects a simultaneous deposition ofthe separate loads in each cycle, and the energization-affecting meansincludes timing cam means operated with said conveyor means foroperating the depositing means in accordance with the linear speed ofsaid conveyor means.

3. The structure defined in claim 2 including a safety electric circuitassociated with the depositing means and the conveyor means for stoppingthe latter in the event said depositing means fails to deposit a load ofmaterial on operation thereof by the cam means.

4. The structure defined in claim l in which the correlating meanseffects intermittent operation of the conveyor means and includes meansfor rendering the depositing means operative when said conveyor means isstopped and means for rendering said depositing means inoperative duringmovement of said conveyor means.

5. The structure defined in claim 4 including a safety electric circuitassociated with the depositing means and the conveyor means formaintaining the latter stopped until the depositing means deposits allof the loads of material in any cycle.

6. The structure defined in claim l including a safety electric circuitassociated with the depositing means and the conveyor means forpreventing operation of the latter on failure of said depositing meansto deposit a load of material in any cycle.

7. Material-blending apparatus comprising: a plurality ofmaterial-feeding machines, each arranged to deliver material therefrom;a plurality of equally-spaced equilength material-receiving means, onefor each of said machines and positioned to receive material deliveredthereby; means operable by the weight of a predetermined load of fibersin each separate material-receiving means for stopping the delivery ofmaterial from the corresponding machine; discharge means for each ofsaid material-receiving means; movable collecting conveyor means forreceiving, on separate equi-length sections thereof, the separate loadsof fibers discharged from said material-receiving means; and meanscorrelating the operation of all of said discharge means with theoperation of said conveyor nieansfor causing automatic continualintermittent operation of each of said discharge means and for causingeach such operation to deposit the resultingly discharged load ofmaterial on said conveyor means in substantially coextensive overlyingrelation with a load of material previously deposited on said conveyormeans from an adjacent material-receiving means, said correlating meansincluding an electric circuit and means affecting the energization ofsaid circuit each time said conveyor means moves the same predetermineddistance.

8. The structure defined in claim 7 including means interposed betweeneach of the material-receiving means and the conveyor means forreceiving each discharged load of material and uniformly distributingsaid load over a length of the conveyor means equal to the distancebetween the discharged but undistributed loads plus the length of areceived but undistributed load.

9. The structure defined in claim 7 in which the ends of the conveyormeans equi-length sections are substantially contiguous, and includingmeans located between each of the material-receiving means and theconveyor means for receiving each discharged load of material anduniformly distributing said load over a said section of said conveyormeans.

10. The structure defined in claim 7 including a distributing conveyorpositioned between each material-receiving means and the collectingconveyor means and arranged to receive each load of fibers dischargedfrom the said material-receiving means and separately discharge eachsaid discharged load from one end of said distributing conveyor fordirect distribution over a said section of said collecting conveyormeans, the length of said distributing conveyors being substantiallyequal to the lengths of the separate said loads received thereon, andthe length of each said load divided by the distance between the saiddischarge ends of said distribution conveyors being substantially equalto the linear speed of said distributing conveyors divided by the linearspeed of said collecting conveyor means.

ll. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequally-spaced fiber-receiving containers, one for each of said machinesand positioned to receive fibers delivered thereby, each said containerhaving a bottom dumping door; means operable by the weight of apredetermined load of fibers in each separate said container forstopping the delivery of fibers from the corresponding machine; meansfor opening each said door to dump each said load of fibers from eachsaid container; a continuously-operating movable collecting conveyorextending beneath said containers for receiving, on equi-length sectionsof said conveyor, the separate loads of fibers dumped from saidcontainers; and means correlating the operation of said door-openingmeans with the operation of said conveyor for causing each operation ofeach door-opening means to deposit the resultingly dumped load of fiberson said conveyor in substantially coextensive overlying relation with aload of fibers previously dumped on said conveyor from an adjacent con-17 tainer, said correlating means including an electric circuit andmeans affecting the energization of said circuit each time said conveyormoves the same predetermined distance.

12. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequally-spaced Eber-receiving means, one for each of said machines andpositioned to receive fibers delivered thereby; means operable by theweight of a predetermined load of fibers in each separatelfiber-receiving means for stopping the delivery of fibers from thecorresponding machine; means for simultaneously discharging all saidloads from all said fiber-receiving means; continuously-operatingmovable collecting conveyor means for receiving, on separate equi-lengthsections thereof, the separate loads o-f bers discharged from saidfiber-receiving means; and means correlated with said conveyor means forcyclically operating said discharge means to cause each of theresultingly discharged loads to be deposited on said conveyor means insubstantially coextensive overlying relation with a load previouslydeposited on said conveyor means from an adjacent fiber-receiving means.

13. The structure defined in claim 12 including a safety electriccircuit associated with said conveyor means and said discharge means forpreventing operation, of the latter by the correlated means and forstopping said conveyor means in the event the predetermined loads offibers have not been received in all of the fiber-receiving means.

14. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequally-spaced fiber-receiving means, one for each of said machines andpositioned to receive fibers delivered thereby; means operable by theweight of a predetermined load of fibers in each separatefiber-receiving means for stopping the delivery of fibers from thecorresponding machine; means for simultaneously discharging all saidloads from all said fiber-receiving means; continuously-operatingmovable collecting conveyor means for receiving, on separate equi-lengthsections thereof, the separate loads of fibers discharged from saidfiber-receiving means; means correlated With said conveyor means foroperating said discharge means to cause each of the resultinglydischarged loads to be deposited on. said conveyor means insubstantially coextensive overlying relation with a load of fiberspreviously deposited on said conveyor means from an adjacentfiber-receiving means; and means automatically operable upon thedischarge of said loads from said fiber-receiving means for restartingthe delivery of bers from said machines.

15. The structure defined in claim 14 in which the automatic meansincludes means for delaying the restarting of the delivery of fibers fora predetermined interval of time after the discharge of the loads fromthe fiberreceiving means.

16. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequally-spaced fiber-receiving means, one for each of said machines andpositioned to receive fibers delivered thereby; means operable by theWeight of a predetermined load of fibers in each separatefiber-receiving means for stopping the delivery of fibers from thecorresponding machine; means for simultaneously discharging all saidloads from all said fiber-receiving means; continuously-operatingmovable collecting conveyor means for receiving, on separate equi-lengthsections thereof, the separate loads of fibers discharged from saidfiber-receiving means; means correlated with said conveyor means foroperating said discharge means to cause each of the resultinglydischarged loads of fibers to be deposited on said conveyor means insubstantially coextensive overlying relation with a load of fiberspreviously deposited on said conveyor means from an adjacentfiberreceiving means; and automatic means for halting said conveyormeans and preventing operation of said discharge means upon actuation ofsaid correlated operating means before all said fiber-receiving meanshave had their corresponding predetermined loads delivered thereto andfor operating said discharge means and restarting said conveyor meanswhen all said fiber-receiving means have had their correspondingpredetermined loads delivered thereto.

17. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequally-spaced fiber-receiving means, one for each of said machines andpositioned to receive fibers delivered thereby; discharge means for eachof said fiber-receiving means; means operable by the weight of apredetermined load of fibers in each separate fiber-receiving means forstopping the delivery of fibers from the corresponding machine and foroperating the corresponding discharge means; a movable collectingconveyor for receiving, on separate equi-length sections thereof, theseparate loads of fibers discharged from said fiber-receiving means; andmeans correlating the operation of said conveyor and the operation ofsaid machines to automatically cause alternate operation of saidconveyor and said machines to effect a delivery cycle of all of saidmachines and Ito cause each operation of each said discharge means todeposit the resultingly discharged load of fibers on said conveyor insubstantially coeXtensive overlying relation with a load of fiberspreviously deposited on said conveyor from an adjacent fiberreceivingmeans, said correlating means including an eletric circut and meansatfecting the energization of said circuit each time said conveyor movesa predetermined distance and each time all of said discharge means areoperated.

18. The structure defined in claim 17 including a distributing conveyordisposed between each ber-receiving means and the collecting conveyorand operable with the latter, each said distributing conveyor beingarrange/.i to receive each load of fibers discharged from thecorresponding fiber-receiving means and separately discharge each saiddischarged load from one end of said distributing conveyor for directdistribution over a said section of said collecting conveyor, the lengthof said distributing conveyors being substantially equal to the lengthsof the separate said loads received thereon, and said length of eachsaid load divided by the distance between the said discharge ends ofsaid distributing conveyors being substantially equal to the linearspeed of said distributing conveyors divided by the linear speed of saidcollecting conveyor.

19. Fiber-blending app-aratus comprising: -a plurality of liber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequally-spaced fiber-receiving means, one for each of said machines andpositioned to receive fibers delivered thereby; fiber-discharging meansfor each of said fiber-receiving means; means operable by the Weight ofa predetermined load of fibers in each separate fiber-receiving meansfor stopping the delivery of fibers from the corresponding machine andfor operating the corresponding discharging means; a movable collectingconveyor for receiving, on separate equi-length sections thereof, theseparate loads of fibers-discharged from said fiber-receiving means;means automatically operable on the discharge of all said loads from allsaid fiberreceiving means for starting said conveyor; means for stoppingsaid conveyor after the latter has travelled a distance equal to thelength of a load thereon plus the distance between adjacent loadsthereon; and means for restarting the delivery of fibers from all saidmachines when said conveyor stops.

20. In weighing apparatus the combination comprising: a Weighing scalehaving a load-supporting beam; a Weigh pan supported on said beam, saidscale being adjustable to exactly balance when said pan is empty;magnetic means secured on said beam; a magnet mounted independently ofsaid scale in position to attract said magnetic means and urge said beamto move in a direction to cause said pan to rise; fixed abutment meansengageable with said beam for maintaining the latter in its exactlybalanced position against the attractive force between said magnet andsaid magnetic means; and means for varying said attractive force wherebya predetermined load in said pan will cause movement of said beam in theopposite direction.

21. The structure defined in claim in which the means for varying theattractive force comprises means [mounted] moving said magnet foradjustment toward and away from the magnetic means.

22. The structure defined in claim 20 including second fixed abutmentmeans spaced from said beam in the said balanced position thereof andenageable thereby for stopping movement of said beam in the saidopposite direction to maintain the magnetic means within the effectiveattractive range of the magnet.

23. In Weighing apparatus the combination comprising: weigh pan means;bottom dumping door means hinged to said pan means; a permanent magneton one of said means; and a direct current electromagnet on the other ofsaid means, one of the poles of said permanent magnet being positionedadjacent one of the poles of said electromagnet when said door means isclosed, whereby, when said adjacent poles are of opposite polarity, saiddoor means is held closed by magnetic attractive force and, when saidadjacent poles are of like polarity, said door means is held open bymagnetic repelling force.

24. The structure defined in claim 23 including counterbalance means onsaid door means for barely maintaining the latter closed in the absenceof said permanent magnet.

25. The structure defined in claim 23 in which the permanent magnet ismounted on the door means and the electromagnet is mounted on the weighpan means.

26. Material-blending apparatusv comprising: a plurality ofmaterial-feeding machines, each arranged to deliver material therefrom;a plurality of equally-spaced equi-length material-receiving meansspaced apart a distance substantially equal to a multiple of the lengthof each said means, one for each of said machines and positioned toreceive material delivered thereby; means operable by the weight of apredetermined load of material in each separate said material-receivingmeans for stopping the delivery of material from the correspondingmachine; discharge means for each of said material-receiving means;movable collecting conveyor means for directly receiving the separateloads of material discharge from said material-receiving means; andmeans correlating the operation of said discharge means with theoperation of said conveyor means for causing each operation of each saiddischarge means to deposit the resultingly discharged load of materialon said conveyor means in substantially coextensive overlying relationwith a load of material previously deposited on said conveyor means froman adjacent material-receiving means, and for causing the ends of allthe loads dumped on said conveyor means from each saidmaterial-receiving means to be substantially contiguous.

27. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequi-length fiber-receiving containers spaced apart a distancesubstantially equal to a multiple of their lengths, one for each of saidmachines and positioned to receive fibers delivered thereby, each' meanswith the operation of said conveyor means for causing each operation ofeach door-opening means to deposit the resultingly dumped load of fiberson said conveyor in substantially coextensive overlying relation with aload of fibers previously dumped on said conveyor from an adjacentcontainer, and for causing the ends of all of the loads dumped on saidconveyor from each said berreceiving means to be substantiallycontiguous.

28. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequi-length fiber-receiving means spaced apart a distance substantiallyequal to a multiple of the length of each said means, one for each ofsaid machines and positioned to receive fibers delivered thereby; meansoperable by the weight of a predetermined load of fibers in eachseparate said fiber-receiving means for stopping the delivery of fibersfrom the corresponding machine; means for simultaneously discharging allsaid loads from all said fiber-receiving means; movable collectingconveyor means for directly receiving the separate loads of fibersdischarged from said fiber-receiving means; and means correlated withsaid conveyor means for periodically operating said discharge means whensaid conveyor means travels a distance substantially equal to the lengthof a load of fibers deposited thereon.

29. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequi-length fiber-receiving means spaced apart a distance substantiallyequal to a multiple of the length of each said means, one for each ofsaid machines and positioned to receive fibers delivered thereby; meansoperableby the weight of a predetermined load of fibers in each separatesaid fiber-receiving means for stopping the delivery of fibers from thecorresponding machine', means for simultaneously discharging all saidloads from all said fiber-receiving means; movable collecting conveyormeans for directly receiving the separate loads of fibers dischargedfrom said liber-receiving means; means correlated with said conveyormeans for periodically operating said discharge means when said conveyormeans travels a distance substantially equal to the length of a load offibers deposited thereon; and means automatically operable upon thedischarge of said loads from said fiber-receiving means for restartingthe delivery of fibers from said machines.

30. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequi-length fiber-receiving means spaced apart a distance substantiallyequal to a multiple of the length of each said means, one for each ofsaid machines and positioned to receive fibers delivered thereby;discharge means for each of said fiber-receiving means; means operableby the weight of a predetermined load of fibers in each separate saidfiber-receiving means for stopping the delivery of fibers from thecorresponding machine and for operating the corresponding dischargemeans; a movable collecting conveyor for directly receiving the separateloads of fibers discharged from said fiber-receiving means; and meanscorrelating the operation of said conveyor and the operation of saidmachines for causing alternate operation of said conveyor and saidmachines and for causing said conveyor to travel a distancesubstantially equal to the length of a load of fibers at each operationof said conveyor.

31. Fiber-blending apparatus comprising: a plurality of liber-feedingmachines, each arranged to deliver fibers therefrom; a plurality ofequi-length fiber-receiving means spaced apart a distance substantiallyequal to a multiple of the length of each said means, one for each ofsaid machines and positioned to receive fibers delivered thereby;fiber-discharging means for each of said fiber-receiving means; meansoperable by the weight of a predetermined load of fibers in eachseparate said fiber-receiving means for stopping the delivery of fibersfrom the corresponding machine and for operating the correspondingdischarging means; a movable collecting conveyor for directly receivingthe separate loads of fibers discharged from said fiber-receiving means;means operable on the discharge of all said loads from all saidliber-receiving means for starting said conveyor; means for stoppingsaid conveyor after the latter has travelled a distance substantiallyequal to the length of a load thereon; and means for restarting thedelivery of bers from all said machines when said conveyor stops.

32. In [weighting] weighing apparatus the combination comprising: abalancing scale beam; a load holder therefor; means balancing said scalewhen said load holder is empty; and magnetic means exerting anattractive force on said scale beam for maintaining the latter againstunbalancing movement except by a predetermined weight of material insaid load-holder; and means mounting said magnetic means for adjustmenttoward and away from said beam to vary said attractive force.

[33. Apparatus for use in proportioning different fibers to be blendedcomprising a plurality of machines for concurrently feeding, Weighingand discharging predetermined amounts of each of a plurality of iibersin successive batches, a movable conveyor for receiving said batches,each of said machines including. a fiber feeder and scale meansincluding a receptacle disposed to receive and weigh bers delivered bysaid feeder, automatic means to discharge weighed batches of fibers fromthe receptacles, said means including an electrical circuit cooperatingWith said movable conveyor and said receptacles for delivering thebatches of fibers from the latter onto one another in superposed layerson the conveyor while it is moving, said conveyor serving to transportsuch layers and means to insure maintenance of the predeterminedpercentages of the several different bers in similar sucssive batches,said means including an electrical circuit which is operative tode-energize the receptacledischarging means when less than thepredetermined amount of any of the several fibers has been weighed] 34.Material-blending apparatus comprising: movable collecting conveyormeans; automatic and continuallyoperating means for depositing inrepetitive cycles a plurality of separate loads of diiierent materials,each of a predetermined weight, on separate equi-length sections of saidconveyor means; means correlating the operation of said depositing meanswith the operation of said conveyor means to cause each said load to bedeposited in substantially coeXtensive overlying relation with a loadpreviously deposited on a said section of said conveyor means by anadjacent depositing means; and a safety electric circuit associated withsaid depositing means and with said conveyor means for preventingoperation of the latter on failure of said depositing means to deposit aload of material in any clcle.

35. Weighing apparatus comprising: a scale beam; a load holder supportedthereon; a counter-weight adjustably mounted on said beam; magneticmeans positioned to exert an attractive force on said beam to urge thelatter to move in the same direction it is urged by said counterweight,whereby said beam will not move as a load in said holder approaches aweight suicient to overcome the forces exerted by said counterweight andby said magnetic means but moves with a snap action when the loadattains the overcoming Weight; and means mounting said magnetic meansfor adjustment toward and away from said beam to vary said attractiveforce.

36. Weighing apparatus comprising: a scale beam; a load holder supportedthereon; a counterweight adjustably mounted on said beam; magnetic meanspositioned to exert an attractive force on said beam for supplementingthe counterbalancing effect of said counterweight, whereby said beamwill not move as a load in said holder approaches a weight suiicient toovercome the forces exerted by said counterweight and by said magneticmeans but moves with a snap action when the load attains the overcomingweight; and means mounting said magnetic 22 means for adjustment towardand away from said beam to vary said attractive force.

37. Weighing apparatus comprising: a scale beam; a load holder supportedthereon; counterbalancing means associated with said beam including anadjustable counterbalance weight and magnetic means exerting anattractive force eifective on said beam; and means mounting saidmagnetic means for adjustment toward and away from said beam to varysaid attractive force.

38. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines disposed in d row, euch arranged to deliver fibers therefrom; aplurality of equi-size fiber-receiving means, one for each of saidmachines and positioned to receive fibers delivered thereby; meansoperable by the weight of o predetermined loud of fibers in eachseparate fiber-receiving medns for stopping the delivery of fibers fromthe corresponding machine; means for simultaneously discharging all saidloads from all said fiber-receiving means; movable collecting conveyormeans for directly receiving, on separate equi-length sections thereof,the separate loods of fibers discharged simultaneously from all of saidfiber-receiving means; means correlated with said conveyor means forperiodically operating said discharging means each time said conveyormeans travels d distance equal to 'the length of a load of fibersreceived thereon, whereby the loads of fibers discharged successivelyfrom euch one of said fiber-receiving means are deposited on saidconveyor means in end-to-end contiguous relation and in overlyingrelation with the loads of fibers deposited on said conveyor means froman adjacent fiber-receiving means; means automatically operable upon thedischarge of said loods from said fiber-receiving means for rte-startingthe delivery of fibers from said machines; and automatic means forhalting said conveyor means and rendering said discharging meansinoperative upon actuation of said correlated operating means at a timewhen any fiber-receiving means has received less than its predeterminedload of fibers.

39. The structure defined in claim 38 in which the automatic meansincludes means for operating the discharging means and re-starting theconveyor means when all the fiber-receiving means have received theirpredetermined loads of ybers.

40. The structure defined in claim 38 in which the correlated meansincludes an electrical switch operable by com means driven wirh theconveyor means.

41. The structure defined in claim 39 in which the automatic meansincludes an electrical circuit having switches therein, one associatedwith each fiber-receiving means and operable by receipt therein of itspredetermined load of fibers.

42. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines disposed in a row, each arranged t0 deliver fibers therefrom; dplurality of equisize fiber-receiving means, one for each of saidmachines and positioned to receive fibers delivered thereby; meansoperable by the weight of o predetermined load of fibers in eachseparate fiber-receiving means for stopping the delivery of fibers fromthe corresponding machine; means for simultaneously discharging all saidloads from all said fiber-receiving means; movabley collecting conveyormeans for directly receiving, on separate equi-size sections thereof,the separate loads of fibers discharged simultaneously from dll of saidfiber-receiving means; means correlated with said conveyor means forperiodically operating said discharging means each time said conveyormeans travels a predetermined distance to cause the loods of fibersdischarged successively from each one of said fiber-receiving means tobe deposited on separate contiguous sections of said conveyor means andin overlying relation with the loads of fibers deposited on saidconveyor means from an adjacent fiber-receiving means; meansautomatically operable upon the discharge of said loads from scidfiber-receiving means for re-starting the delivery of fibers from saidmachines; und automatic means for halting said conveyor means andrendering said discharging means inoperative upon actuation of saidcorrelated operating means at a time when any fiberreceiving means hasreceived less than its predetermined load of fibers.

43. The structure defined in claim 42 in which the autou matic meansincludes means for operating the discharging means and re-starting theconveyor means when all the fiber-receiving means have received theirpredetermined loads of fibers.

44. The structure defined in claim 42 in which the correlated meansincludes an electrical switch operable by cam means driven with theconveyor means.

45 The structure defined in claim 42 in which the automatic meansincludes an electrical circuit having switches therein, one associatedwith each fiber-receiving means and operable by receipt therein of itspredetermined load of fibers.

46. F iber-blending apparatus comprising: a plurality of fiber-feedingmachines disposed in a row, each arranged to deliver fibers therefrom; aplurality of equi-size fiberreceiving means, one for each of saidmachines and positioned to receive fibers delivered thereby;fiber-discharging means for each of said fiber-receiving means; meansoperable by the weight of a predetermined load of fibers in eachseparate said fiber-receiving means for stopping the delivery of fibersfrom the corresponding machine and for operating the correspondingdischarging means; a movable collecting conveyor for directly receivingon separate equi-length sections thereof the separate loads of fibersdischarged from said fiber-receiving means; means automatically operableon the discharge of all said loads from all said fiber-receiving meansfor starting said conveyor; means for stopping said conveyorautomatically after the latter has travelled a distance substantiallyequal to the length of a load of fibersthereon; and means forre-starting the delivery of fibers from all said machines automaticallywhen said conveyor stops, whereby the loads of fibers dischargedsuccessively from each one of said fiber-receiving means are depositedon said conveyor in end-to-end contiguous relation and in overyingrelation with the loads of fibers deposited on said conveyor from anadjacent fiber-receiving means.

47. Fiber-blending apparatus comprising: a plurality of fiber-feedingmachines disposed in a row, each arranged to deliver fibers therefrom; aplurality of equiesize fiberreceiving means, one for each of saidmachines and positioned to receive fibers delivered thereby;fiber-discharging means for each of said fiber-receiving means; meansoperable by the weight of a predetermined load of fibers in eachseparate said fiber-receiving means for stopping the delivery of fibersfrom the corresponding machine and for operating the correspondingdischarging means; a movable collecting conveyor for directly receivingon separate equi-size sections thereof the separate loads of fibersdischarged from said fiber-receiving means; means automatically operableon the discharge of all said loads from all said fiber-receiving meansfor starting said conveyor; means for stopping said conveyorautomatically after the latter has travelled a predetermined distance;and means for re-starting the delivery of bers from all said machinesautomatically when said conveyor stops, said predetermined distancebeing such that the loads of fibers discharged successively from eachone of said fiber-receiving means are deposited on separate contiguoussections of said conveyor and in overlying relation with the loads offibers deposited on said conveyor from an adjacent fiberreceiving means.

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